Spark-plug



A. J. PERHON.

SPARK PLUG.

v APRLIC-ATION LED JUNE lll. 1920.

Reissued Sept 14, 1920.

To @ZE wiwi/z. it muy concern.' p

Be it known that l Ann-Kansen Josnrn IninioN, a citizen ot' the United States,` and a resident of Sparta, in the coun .y oit Montain new and vuseful Improvements in Spark-Plugs, oit which 'the following is a speoilicatjon.

My invention rela-tes to imlrrovenients in spark pilisgs, and it consists in the construction, coinliiination and arrangement of the parts. substantially as herein described and. claimed. n. y

-An object ot my i ivention is to provide a .spark plug hz'iving an aimost entirely closedv shell for the purpose of protecting the central electrode, the door ot the shell being disposed at an angie to canse anjyv possihie. accumulation or' oii in the shell, to run 'to the drip point beneath the eiectrode, thus keeping the interior ot the shell clean.

A nothf object ot the invention is to provide a, spH` k ping inc" Lading a sheli which entirel.v closed with the exception of a single ciectrode .slot into which the point or the central eiectrode extends to provide the spark grip, the central elect :ide and a portion of the porcelain being ronde-square to prevent tin-ning; and disalining` the point of the central. electrode in screwing; the packing nut down.

A. further object oi' tile invention. is to provide a spark plug having the restores hereinbefore described, and including a mark whereby the location or" the electrode slot may he determined, for purposes ot' positioning the spark gap.

Other objects and advantages will appear in the followingI specieation, reference being had to the accompanying drawing in which:--

view illustrating how' theinolined floo acts as a reflector;

Fig. 5 is a detail perspective view showing the core and the shell of the spark plug separated, the sheil being shown in section;

Fig. 6 is a detail sectional view iliust 'atingv a slight Ilnrpidification, andJ UNITED STATES roe and State of Wisconsin, have made cer- Figure 'l is a vertical section ot the im PiTENT PFSE.

ALEXANDER JSEPH PERRON, OF SFAR/EA, "WSCONSINI eraan-PLUG.

Speoication of Reiss-lied Letters Patent. Iig/issued Sept. '1920.--

Originel No. 1,308,101', dated .uy I., i919, Serial No. 249,888, filed August 14, 1918. Application for.)l

reissue Sile/. ."sune 11, 1920. Serial No. 38834K.

Fig. l, but showing a modied structure in the core and the niouiiting therefor.

Oneof the important features of the spark plug lies in the construction ot' 'the metal shell l, which7 `when the parts of the spark plug are assembled is entirely closed on the bottom with the exception of a single narrow electrode slot 2.

The floor B et the shell l is disposed an angie as clearly shownin Figs. l and ii, in order to cause the drainage of any such substance as oil toward the drip point 4 Where the drop .torn as shown in Fig. et. In the iirst place, hy almost entireljyT closing the shell l, the iilling of the spark plug around the central electrode. 5 by means of oil, carbon and gas is almost entirely pre vented.

Anyoil that may [ind its Way into the shell l through the slot 2 will quickly 'run out because it cannot stand on the inclined fioor 3. The shell l has a threaded body 6 by means of which 'the spark plugis screwed into the head of an engine.

The shell 1 has a bore of al number 'of electrode, when the packing `nut l1 is screwed down.

A boss 12 on the porcelain core tits in the count-arbore 13 of the shell l. This counterbore is threaded and receives the packing nut 11. Gaskets lll# are located on the upper and lower sides of the hoss 12 and are intended to forni a tight joint 'when the nut is screwed down.

The central electrode 'is square in. cross section so that it cannot turn' in the porcelain core 10. A collar l5 on the electrode prevents it from dropping out. The collar 1s molded in the core as shown. The spa-rk point of the centrai electrode is at the end loo core and the square portion 8 of the shell is.

to keep .the spark point of the central electrode in the true position at thel head of the 'electrode slot andprevent the disalinement of the-'spark point when the [packing nut l1 is 'screwed down.

In order that the location of the-spark gap may be ascertained by simply looking at the plug when it is in position in the .en-

gine cylinder, a suitable mark 16 is made on the exposed part of the shell directly inline with the electrode slot 2. Besides serving to drain the shell of oil, the inclined'lioor 3 acts as a reflector. to the force. of the explosin.

This feature is illustrated'. in Fig. 4 by the arrows. The gas createdby the explosion is made to' sweep back out of the electrode slot vv2 and across the spark point of--the electrode, ,thereby clearngtheslot and tending to keep 2Q the spark pointclean.

The modification in Fig. 6 consists simply of providing a minute drain hole 2 in alinement with the inclined'floor 3. 'In this case closed to even agreater'extent than is the -important elements of the invention, 21e.,-`

' 35 the'const'ru'ctio'n ofthe shell `l, a slight'dethe' electrode slot 2 ismade just large enough to accommodate the spark pointof thecentral electrode. In this form of the invention -it Will be observed that the 'shell 1 is casein Fig.'` 1; it is rthe purpose of the in'- vention to inclcse the central electrode as,

much as possible for the purpose of protection.

The modification inFig. 7 embodies the parture being made in the construction of the. electrodes in that a fixed electrode A17 is formed at the head of the electrode slot'.

This -formation enables the location of the" spark'point of the central electrode 5 even farther inside of the shell In this form of the meermaals sum1 electrode forms a part of the central metallic core 18,-which is of the vsame general appearance of the porcelaincore 10. 'A sleeve 19 vand a bushing 2O or` insulating and heat its side, so'as to exclude 'substances frein the interior ofthe shell around the electrcde.

resisting material, supports the metallic core 18 in the 'shell of the spark plug.

The invention exeln-pliiiesa spark plu(T in Iwhich the shell containing the central e ec.- trode is closed, except for a hole or slot in While the construction and arrangement of the spark plug herein described and illus-- trated'is that of a` generally preferred form', obviously slight modifications and changes may be made'without departing from th spirit of claims.

vHaving thus described the invention, what I claim' as new and desire to secure by Letters Patent, is :l

1. A spark plug comprising a shell haw ing anannular wall with a'hole-.in its lside hole to exclude substances'froin the interior the invention or the scope of the and a closed bottom and substantially-closed except for said hole to exclude. substances from the interior of the shell, and a central' electrode contained'in and insulated from said shell, having. a terminal -to form a spark gap between the shell and the electrode.

2l A -sparkplug comprising a shell having' acylindrical vWall with a vertically e'xtending hole in its side and a closed bottom,

iand a central electrode withinfthe shell, havinge terminal to forni a spark gap adjacent said opening, the'shell being substantially closed around the electrode except for saidr of the shell. A

Ina spark plug, the combination of a shell provided :with an, annular wall having anelectrode hole therein and a closed bottom whereby substances will be excluded from the interior of the shell, a central electrode in the shell having a terminal extended to form a. spark gap adjacent the hole, an in# sulating` sleeve in which the electrode is se'- cured, andan interfitting connection between the core and thev shell whereby they will be secured against relative rotation and be kept in correct operative relation.

la A spark plug,'compr isi ng a central elec* I trode, andA ashell having unl-electrode slot for receiving the point of said electrode to 'form they spark gap, said sl iell'being ;'v er1- tir'ely closed with the exception of-said slot` for the protectionof said electrode and; the

exclusion of substances from the interior of. the shell, vand having an inclined floor acting as arefiector' to expel the gas and clear said slot and spark point.

A spark plug, comprisingr a central elec- -t-rode anda shell having an electrode slot for receiving the point of said electrodeto forni' the spark gap, said vshell being entirely closed-with the exception of said slot for the protection of said electrode, and being pro# vided with a floor inclined upwardly from the base of saifl'slot, to form an oil drip point below said slot and to insure the drainage. of the spark plu-g.v

6. In. a spark plug, atively narrow and vertically disposed electrode slot, said shell being entirely closed with the exception of said slot vand being pro-' vided with anon-cir`cular portion in the bore of the shell, a centralelectrode of` non-circuf vlarcross section having the point turned into thef'electrode slotto forni the spark gap, andv an insulatingr core l1avingsaid'-electrcde elnbedded therein and provided with 'a non? circular endit'o iit in said n m.circular pertion and yprevent'the disalineinent et the bling par '7. ln a spa ticaily. dispe and a Hoer slanting up Fi'oml the base or said slot tu drain shellrc'lf oil te adrip peint Vielbw 'a shell havingv a'rel@ haring a ver leo tile Si0t,' thel bere 'fsaid Shel-1 l'mxfing :ino-DT vCirculaiportion'- :ind the. exterior4 oi the Shell Ahavil'lg armati; vin vertical linemeht v Withj--the electrode slet 'for thedeteifmina-j tion offthe spark gap when the ping is in :place in' u cylinder, a central eiectrode of noxi-crularcrss, Sectn iiving the point turned into-said slot to form thespark gap,

anilisulating core having the v electrode em!r4 bedded therein, the'eleetl'odehaving' i; .C01-

lar to 'prevent'v it fm1 n` dropping out, saidv core inludig non-circula;` end fitting in.

said non-circular portion of the Shell to 'revent turning-of the c ore @and the meying, the shell having a l`Wardly from" op'e'ing to cause fluidv to run dDwn tofsaid Qpening,'and being enpacking mity zirjanged yno 'bind Said -co're'in'- place.

' S. A sparkling, ing an electrode slet fo'rm @italy closed' with the exception 0f s aid' Slot,

and' a central electljde h'aving'afspark point A turned toward theltop o f the lS101: to form the spark gzip.

comprising ay shell hav? Y ng a drauifopem oor' slantin'g -up- 

